Maxxis mountain bike tire casings are notorious for their use of abbreviations like EXO, EXO+, DD, 60 TPI, 120 TPI and so on. We’re here to explain all of it in plain English to make your tire choice easy.
Luckily for us, Maxxis recently simplified and combined their casings and puncture protections. There are now four distinct casings:
- EXO = soft 120 TPI with sidewall protection
- for Light-duty trail and Cross Country riding
- EXO+ = stiffer 60 TPI casing with EXO sidewall insert
- for All-mountain trail riding
- DoubleDown (DD) = thick Dual Ply 120 TPI casing
- for Enduro, DH, and e-bikes
- Downhill (DH) = thick, stiff Dual Ply 60 TPI casing
- for Downhill racing and long-travel e-bikes
Each casing option now has the same “EXO” butyl sidewall insert. The main puncture protection comes from the casing thickness.
The only difference is the casing construction: 120 TPI (thin), 60 TPI (thicker) and dual plys (double layer) versions for each of them (DD and DH).
The most common ones are 60 and 120 TPI, with DH and DD only available for tough gravity tires.
Luckily Maxxis pre-selects casings for you. EXO and EXO+ for XC and Enduro, DD and DH for aggressive gravity tires.
Only popular all-rounder tires like Minion and Assegai are available in all casings.
That’s because these casings vary in grip, stiffness, protection and weight. So, depending on the type of riding you do, one casing is better than another. Some are downright wrong – like DD on an XC bike.
EXO and EXO+
Maxxis recently streamlined EXO. The only difference between EXO and EXO+ is now the casing thickness. EXO+ is just a thicker version of EXO.
The added puncture armor is the same. It’s only a question of 60 TPI versus 120 TPI (explained here).
Here is the short version:
120 TPI is lighter and thinner. Thus is better for Cross Country, Trail and Enduro, where weight and comfort are important.
60 TPI is thicker and stiffer, thus ideal for high-impact riding like Downhill and Freeride, where puncture resistance and cornering stability are key.
Those lower TPI casings are generally stiffer and more stable, which is crucial to have the tires not fold over when cornering hard.
There are even thicker, stiffer, heavier casings that are impractical for most trail riding.
This is why Maxxis produces stronger dual layer casings (DD and DH) only for a few select gravity tires.
Double Down & Downhill Casings (Dual Ply)
Double Down (DD) and Downhill (DH) are Maxxis’ dual-ply casings. Meaning the use two layers instead of one to be stiffer, more durable and more flat-resistant
DD is a dual-ply 120 TPI and DH is a dual 60 TPI casing.
This kind of toughness and weight is only useful on aggressive downhill and freeride bikes. Thus, you’ll only find Maxxis’ gravity tires to be available in DD and DH casings.
DD can still be used on Enduro rear tires and Downhill bikes for lighter riders or front tires.
Only DD and DH casings still have have wire beads (optionally).